In this double-blind randomized controlled trial, 80 individuals (35-65y) with pre-diabetes (IGT/IFG) will receive either a diet containing slow digestible starch (amylose; N=40) or control starch (amylopectin; N=40) for 3 months. Our data in rodents (supported by others) have shown that the ingestion of slow digestible starch: a) enhances the gut microbial profile; b) reduces metabolic endotoxemia; c) increases fermentation and production of butyrate & propionate; d) increases beneficial gut hormones such as GLP-1 and PYY; e) lowers the glycemic load and; f) suppresses appetite Therefore, we propose to feed a slowly digestible starch to simultaneously target several mechanisms known to be important in glucose homeostasis with emphasis on insulin sensitivity, fat oxidation and ectopic fat. We will test the hypothesis that improved composition of the gut microbiota with a daily intake of 45 g of amylose for 3 months in individuals with IGT and/or IFG will in turn improve risk factors for the development of T2DM such as: a) enhancement of insulin sensitivity (FSIGTT; Aim1); b) decrease appetite and food intake (Aim2); c) decrease ectopic fat depots (1H-MRS; Aim1); d) decrease inflammation (serum markers; Aim1) and; e) modify the composition of large intestine microbiota in a metabolically favorable way (Aim3). This dietary intervention approach (addition of slowly digestible starch in yogurts) may prove more tolerable than daily caloric restriction and exercise and therefore more practically applicable for the treatment of T2DM.